That gap in comparative conviction rates is nearly eliminated when there’s at least one black person in the jury pool, the study also reported.

Looking at the effects of race, gender, and age had on jury pools and conviction rates, Duke researchers examined more than 700 non-capital felony cases in Sarasota and Lake counties in Florida from 2000-2010.

The jury pool is randomly selected from eligible residents who are summoned for jury duty that day. The jury pool is made up of 27 members from which attorneys selected six juror plus alternates.

“I think this is the first strong and convincing evidence that the racial composition of the jury pool actually has a major effect on trial outcomes.

Our Sixth Amendment right to a trial by a fair and impartial jury of our peers is a bedrock of the criminal justice system in the U.S., and yet, despite the importance of that right, there’s been very little systematic analysis of how the composition of juries actually affects trial outcomes, how the rules that we have in place for selecting juries impact those outcomes.”

The jury pools of Sarasota and Lake counties were chosen for the study because, Bayer said, the counties provide the most detailed records of court trials than other US counties.

In addition, Bayer said that attorneys don’t have to explain why they might exclude jurors from a criminal trial through a process known as “peremptory challenge.”

No misconduct was found in the cases examined in this study, according to Bayer.

In cases with no blacks in the jury pool, blacks were convicted 81 percent of the time, and whites were convicted 66 percent of the time. The estimated difference in conviction rates rises to 16 percent when the authors controlled for the age and gender of the jury and the year and county in which the trial took place.

When the jury pool included at least one black person, the conviction rates were nearly identical: 71 percent for black defendants, 73 percent for whites.

About 40 percent of the jury pools they examined had no black members and most of the others had one or two black members.

When blacks were in the jury pool, they were slightly more likely to be seated on a jury than whites. The eligible jury population in these counties was less than 5% black.

The forthcoming trial of George Zimmerman in the Trayvon Martin case will likely take place in Seminole County, which is more than two hours away from the counties in this study.

Still, it seems that it’s no accident that this research has been released now, at a time when the American justice system has a great opportunity to address some of its inherent limitations. It will be interesting to see how jury pool dynamics play out in the Martin case and other upcoming trials.